Increased tractor horsepower has resulted in larger implements capable of planting or working a much wider swath in a single pass. Transport of these wide implements from a storage area to a field or from one field to another over roads has become an important design consideration. Some early planters required separate trailers for transport. In addition to the cost of these special-use transport trailers, these planters are limited in length by the practical requirements of having to load the implement on the trailer and to unload it. The time involved with the use of a separate trailer is increased because in loading the implement on the trailer and then in setting up the implement in the new field, the tractor must be unhitched from the implement and then hitched to the trailer, with the reverse procedure followed at the new site. This loss of time can be significant in view of the short time typically available when good planting conditions prevail, particularly when numerous fields must be planted using the same implement.
Other attempts to facilitate transport of larger implements include frames with pivoting wing sections on which row units are mounted which may be vertically folded. When folded, the implement is much greater in height, frequently causing problems when attempting to pass under bridges, through gates and into storage buildings. In addition, even with the two outer wing sections folded, because of the increasing size of agricultural implements, the fixed center section may also restrict transport and storage of the implement.
Still other attempts include lifting and rotating the wings about a pivot point generally in line with the tongue of the tractor. Lift and rotate planters are agricultural implements with wings extending transversely from a tongue when the planter is in a field use. A centralized actuator can lift the wings and attached row units during turning, and can lift further and rotate the wings substantially in line with the tongue for transport of the planter. This provides for a narrower implement that can be driven down most roads and that can pass under most bridges.
However, lift and rotate planters are not without problems. Due to the increased sizes of the wings, during lifting, they may tend to want to rotate or walk, with can increase the strain on the toolbar and components thereof. Furthermore, when the wings increase in length to increase the number of row units attached thereto, the amount of power required by the lifting actuator, as well as the length between the pivot point and the tractor need to be increased.
Therefore, there is a need in the art for an improved agricultural planter that provides for an increased width to increase the number of row units attached thereto, while providing improved systems, apparatus, and methods for lifting and rotating the wings of the planter to allow for turning and transition from a field use and a transport configuration of the planter.